The invention relates to an insertion tube for firing subcaliber ammunition bodies with a high caliber weapon, which is insertable in the loading chamber of the weapon. Further subject matter of the invention forms a weapon with an insertion tube, which is insertable into the loading chamber of the weapon for firing subcaliber ammunition bodies.
Guns with larger caliber weapons, such as artillery, howitzers, etc., are usually operated with split ammunition consisting of the actual projectile and a separate propellant charge. When loading the weapon, first the projectile is inserted and next the propellant charge is inserted from behind through an opened closure device into the loading chamber of the weapons. Upon positioning of the projectile into the loading chamber of the weapon projecting in the firing direction, the projectile adapted to the caliber of the weapon is displaced securely within the loading chamber and closes this in a gas-tight manner on the opening side. After closing of the closure device, the propellant charge can be ignited and the projectile can be fired, whereby upon ignition of the propellant charge, the gas pressure that is provided also can be used in order to close the loading chamber in a gas-tight manner also on the loading side via a sealing element that is effective under pressure effects, often designated as a obturator.
In addition to these specific applications of the weapon, in many situations it also is desired to fire subcaliber ammunition bodies, that is ammunition bodies with a smaller caliber than that of the weapon. For example, in the frame of maneuvers, based on reasons of costs, frequently practice ammunition of a smaller caliber are used, which cannot be fired readily in any event by means of the high caliber weapon.
In this connection, it is known to reduce the caliber of the weapon by means of an insertion tube, which is insertable in the loading chamber of the weapon, in order to temporarily adapt to a smaller caliber of the practice ammunition, which enables the practice ammunition to assume a defined position within the loading chamber and to be fired accurately.
Such insertion tubes for firing practice ammunition typically are smooth-walled tubes, which are well-proven for firing cartridge practice ammunition. The practice ammunition typically consists of a projectile and a propellant charge arranged behind the projectile in a common cartridge housing, which is why upon firing of the practice ammunition, a gas pressure is produced by the cartridge housing in the direction of the opening-side of the weapon, via which the projectile is accelerated out of the cartridge housing.
Problems occur, however, when firing other types of subcaliber ammunition bodies, for example, when firing mortar cartridges, with which a gas pressure forms within the loading chamber of the weapon, which is also directed in the direction of the closure side of the weapon. Because the insertion tube inserted in the loading chamber is typically provided in the closure area of the weapon, sealing elements shield the loading chamber from the effects of pressure. With such ammunition bodies, the danger exists that upon ignition for a mortar cartridge, for example, the sealing element of the loading chamber is not sealed effectively and parts of the gas pressure produced during firing of the weapon move rearwardly.